When sending a duplicated Request To Send (RTS) frames across 40/80/160 MHz channels, Clear To Send (CTS) frames should be returned for the same, or of some channels are busy, a reduced set of channels as the RTS. Further, to ensure that all parties hear and respect the Duration field included in the RTS and CTS frames, the frames should be backwards compatible with legacy protocols. For example, if sending RTS/CTS frame on a 5 GHz channel, a frame should be sent that is compatible with 802.11a (which may be referred to as “11a”). Moreover, using RTS and CTS frames provide the benefit of auto reset of the Network Allocation Vector (NAV). For example, if a receiver receives a RTS but does not receive a corresponding CTS or Data frame for the RTS, the receiver will reset its NAV.
Determining the bandwidth of a RTS can be performed by a digital signal processor (DSP). However, the algorithms can be complicated and prone to errors.